Sudanese police have saved nearly 100 people, including 85 minors, from a network of human smugglers in an operation that highlights the scale of trafficking in Africa, Interpol has said.

The international police organisation said on Monday that it had coordinated Operation Sawaiyan, which was carried out in August by 200 Sudanese officers.

The 94 rescued people originally came from half a dozen countries, comprising Chad, the Democratic Republic of Congo, Eritrea, Niger, Sudan and South Sudan.

"The diversity of nationalities amongst those rescued shows how human trafficking and people smuggling is a truly transnational problem," Interpol's Executive Director of Police Services, Tim Morris, said in a statement.

The United Nations Office on Drugs and Crime (UNODC) reported on 31 July that children and young people make up one-third of the human trafficking in Eastern Africa.

Grave economic and political conditions in Sub-Saharan Africa push thousands to flee their home countries, with Sudan serving as a midpoint before the final departure pad towards Europe.

Police also seized $20,000, believed to have been paid in ransom for the abduction of a migrant who was saved during the operation, the statement said.

Fourteen suspects, including 12 women and two men, were arrested at the beginning of the investigation. The operation took place in several parts of the Sudanese capital Khartoum, including its international airport as well as some open-air gold mines.

"Many of the minors rescued during Operation Sawiyan were discovered working under extreme conditions in illegally-operated gold mines, where children as young as 10 were also handling dangerous chemicals and substances such as mercury and cyanide," the statement said.

According to a recent study issued by the UNODC, Khartoum is a vital crossing point in at least five major smuggling paths, as well as several smaller northward routes in Africa, connecting the Horn of Africa via land to North Africa.